Topples

Like a domino that falls over when tapped by a playing card, a topple landslide may occur when a cliif is eroded, by waves at its base, continually losing strength and eventually the rock mass rotates forward and falls downward.

Topple failures involve the forward rotation and movement of a mass of rock, earth or debris out of a slope.

This kind of slope failure generally occurs around an axis (or point) at or near the base of the block of rock.

A good example of a site experiencing topple failures is Aldborough, UK.

A topple often results in the formation of debris or a debris cone at the base of the slope; this pile is called a talus cone. New talus cones don't have any plants growing on them. Old talus cone can have weeds and even trees on them.

A topple landslide 'in progress' at Portland, Dorset. The arrow points to a forward-tilted rock mass that will eventually fall down the cliff face..